Project description:Many sulfur-oxidizing prokaryotes oxidize sulfur compounds through a combination of initial extracytoplasmic and downstream cytoplasmic reactions. Facultative sulfur oxidizers adjust transcription to sulfur availability. While sulfur-oxidizing enzymes and transcriptional repressors have been extensively studied, sulfur import into the cytoplasm and how regulators sense external sulfur are poorly understood. Addressing this gap, we show that SoxT1A and SoxT1B, which resemble YeeE/YedE-family thiosulfate transporters and are encoded alongside sulfur oxidation and transcriptional regulation genes, fulfill these roles in the Alphaproteobacterium Hyphomicrobium denitrificans. RT-qPCR provided initial evidence that SoxT1A and SoxT1B from H. denitrificans may be intricate components of the oxidation pathway and/or involved in its transcriptional regulation. Here, we extend these analyses with genome-wide mRNA-Seq data for the reference strain, comparing transcription in the absence and presence of 2 mM thiosulfate
Project description:Plants utilize soil sulfate for production of sulfur-containing amino acids that serve as essential dietary sulfur sources for animals. Despite the global nutritional significance of this fundamental metabolic process in nature, transcription factors regulating the plant sulfur assimilation pathways have never been discovered. We isolated sulfur limitation1 (slim1) mutants from Arabidopsis, showing abnormally low expression of SULTR1;2 sulfate transporter, by screening responsiveness of SULTR1;2 promoter-GFP, as an indicator, to sulfur limitation. SLIM1 encoded an EIL-family transcription factor, EIL3. To clarify the siganificance of SLIM1 function in sulfur responsive gene expression, we analyzed the transcriptome profiles in slim1-1, slim1-2 and the parental line under +S and -S conditions. Keywords: comparison of mutant and wild type, sulfur limitation response, nutritional stress response